Storage receptacle for pulverized material



Aug. 17, 1965 w. HERMANNS 3,201,000

STORAGE RECEPTACLE FOR PULVERIZED MATERIAL Filed July 9, 1963 2 Sheets-Sheet 1 WWWW Jn venzor Aug. 17, 1965 w. HERMANNS 3,201,000

STORAGE RECEPTAGLE FOR PULVERIZED MATERIAL Filed July 9, 1965 2 Sheets-Sheet 2 Jnven/ar,

United States Patent F 3 Claims. cl. 222 1s3 To empty receptacles for pulverized material, it is known to provide in the bottom part of the receptacle a flexible non-resilient web whose edges are secured in airtight fashion to the receptacle wall and which is adapted to be curved into the receptacle interior by compressed air, the Web engaging intimately with the receptacle Wall when the receptacle is empty or when the supply of compressed air is interrupted, the receptacle ejecting the material on it to the discharge from the receptacle or into a conveyor chute extending to such discharge when the web is curved in towards the receptacle interior. It is also known for the web to be air-pervious in some parts so that that part of the compressed air blown below the web which is not required to curve the Web passes through the web to loosen the pulverised material thereinto.

Receptacles having a discharging device of the kind webs that bridging occurs in the material and prevents the same from being discharged satisfactorily from the receptacle.

The invention obviates this disadvantage. According to the invention, those parts of the flexible lining web which, when the same is curved inwards into the receptacle, are not loaded or are substantially not loaded by the weight of the pulverized material are made of a finely porous air-pervious substance, while the remainder of the web is impervious to air. For very sticky material, it is advisable to use receptacles which in manner known per se have a funnel-shaped bottom part, the web extending thereinto and into a part of the cylindrical receptacle wall above the "funnel-shaped part, the air-pervious finely porous part of the web being disposed near the funnelshaped part of the receptacle. Some of the compressed air supplied below the web passes through the pores of the air-pervious bottom web partinto the receptacle interior-and therefore into the powdery material-at a place where bridging is particularly liable to happen; even a relatively sticky powdery material is therefore loosened so thoroughly as to be able to discharge satisfactorily.

Horizontal and vertical receptacles for pulverized material according to the invention are illustrated as embodiments in the drawings wherein:

FIG. 1 is a partly sectioned view of a vertical receptacle having a relatively fiat base;

FIG. 2 is a view similar to FIG. 1 but with the web curved in towards the receptacle interior;

FIG. 3 is a partly sectioned view of a Vertical receptacle having a funnel-shaped part at the bottom end;

FIG. 4 is a longitudinal sectional view through a horizontal receptacle, and

FIG. 5 is a cross-section, taken along the line V-V of FIG. 4, through the receptacle illustrated therein.

A receptacle 1 for pulverized material is illustrated in FIG. 1, has a relatively flat base 2, and is formed therein with a central discharge aperture 3. A flexible web which surrounds the aperture 3 is disposed in the receptacle and comprises a top air-impervious part 4 and a bottom airazaleas Patented Aug. 17, 1955 pervious part 5. The top part 4 of the web can be made, for instance, of a plastic foil with reinforcing inserts, while the bottom part 5 can be a finely porous fabric or mesh or the like. The bottom edge of the bottom web part 5 is secured to the receptacle wall near the apertures 3, and the top edge of the top web part 4 is connected in air-tight manner to the receptacle inner wall. A tube 6 which extends through the receptacle wall connects, to a source of compressed air which is not shown, the space between the Web 4, 5 and the receptacle wall. When compressed air is blown through pipe 6 below the web 4, 5, the same curves in towards the receptacle interior in the manner shown in FIG. 2, some of the compressed air passing through the finely porous web part 5 and loosening the pulverized material from below and disengaging it from the smooth walls of the top web part 4.

The receptacle illustrated in FIG. 3 difiers from the receptacle illustrated in FIGS. 1 and 2 in that its bottom part 7 narrows downwards after the fashion of a funnel, and the web parts 4, 5 extend over this funnel-shaped part 7 and a proportion of the cylindrical receptacle Wall above. The finely porous web part 5 is disposed near the funnel-shaped bottom end 7 of the receptacle. The width of the finely porous web part 5 depends upon the nature of the material being conveyed and can be, for instance one-third of the total width of the web 4, 5.

The elongated or horizontal receptacle shown in FIGS. 4 and 5 comprises a cylindrical shell or casing 11 and arcuate end members 13 welded thereto; in the centre of its length the receptacle has a charging manhole 12 at the top, while at the bottom, opposite the manhole 12, is a discharging aperture 14. From the aperture 14, which is formed by a short spigot of square cross-section, a discharge tube 15 extends inside the container along the length thereof to atmosphere. The tube 15 is led through the right-hand end Wall 13 of the receptacle at a place 16 where it is welded to such wall in sealingtight fashion. The tube 15 is closed outside the receptacle by a valve 17 of known construction or the like, so that a connecting spigot is provided. As can be gathered from FIGS. 4 and 5, false floors 19 which extend lengthwise of the receptacle are disposed in a narrow central zone above the floor of the receptacle; the floors 19 meet in the centre of receptacle length at the top edges of the discharge aperture 14 and rise slightly in both directions towards the receptacle end walls 13. Disposed on the floors 19 are four parallel air-pervious hoses 27 which serve as loosening elements. The hoses 27 are closed at the ends near the discharge aperture 14 and are connected at their other ends-i.e., the ends near the receptacle end walls-to risers 28 adapted to be supplied, each by way of a collecting pipe 29 in the valve 30 with compressed air which is supplied to the system through a pipe 31. The action of the loosening elements is known and need not be described in greater detail here.

Extending on both sides of the loosening elements 27 are walls 20, 20 which are vertical over their whole length which are borne by the floors 19 and which are Welded thereto in air-tight fashion. The top edges of the side walls 24 20' are horizontal and are at such a height above the receptacle base as to be slightly higher than the loosening elements 20 at the places where the same communicate with the risers 28. Vertical partitions 24 are provided at the outer ends of the false floors 19 and of the side walls 20, 20' connected thereto and are rigidly welded to such walls and to such false floors at a place 25. The partitions 24 extend over the whole cross-section of the receptacle in the bottom part thereof and are welded in air-tight manner to the inner periphery of the receptacle shell 11. Near the top of the receptacle the partitions 24 merge with a slight inclination into the receptacle end walls 13 and are welded thereto in airtight fashion at a place 26. Extending on both sides of the lateral boundary walls Ztl, 2d of the elements 27 are flexible non-resilient webs 22, 22' which have air-impervious top parts 36, 36' respectively and bottom parts 37, 37' respectively in the form of an air-pervious finely porous fabric or mesh or the like. The webs 22, 22' have their bottom edges 21, 21 secured to the top edges of the lateral boundary walls 20, 29 respectively, and their top edges 23, 23 secured to the receptacle wall 11 below the centre of the receptacle; preferably, the connection between the top edges 23, 23' and the receptacle wall is air-tight. The webs 22, 22' extend between the walls 24 over the whole length of the receptacle but are connected at their ends to the walls 24 along a respective line 35, 35. The lines 35, 35 extend substantially straight between the top edges 23, 23 and the respective bottom edges 21, 21' of the webs. The width of the webs is such that the same, as they hand down from their edges by which they are secured, engage intimately with the receptacle wall and the lateral boundary walls 2%, 2th. The webs 22, 22' therefore form pockets which extend along the length of the receptacle on both sides of the loosening elements 27, and they co-operate with the walls 24, 20,24) and with the false floors 12 to divide a chamber 32 oif from the filling zone of the receptacle. The filling material introduced into the receptacle through the manhole 12 rests on the loosening elements 27 and on both sides thereof on the webs 22, 22'. The space 32 below the webs and the false floors is connected to the compressed air pipe through a pipe 33 and a valve 34.

Operation is as follows:

With the valve 34 closed, the valve 30 is opened and compressed air is blown into the loosening elements 2'7 until the receptacle has been discharged to an extent such that the only material left is in the said pockets on both sides of the elements 27. The valve 34 is then opened to inject lompressed air below the flexible webs 22, 22. The same are therefore lurved in towards the receptacle interior as indicated by chain-dotted lines in FIG. 5, some of the compressed air passing through the steep 'air-pervious bottom parts 37, 37' of the webs 22, 22 respectively and preventing any bridging of the pulverized material between the webs 22, 22'. Once the receptacle has been fully discharged in this way, the valve 30 is closed and the compressed air remaining in the filling zone of the receptacle discharges through the discharge tube 15. The compressed air still present below the webs 22, 22 escapes via the still open valve 34 and loosening elements and via the air-pervious bottom parts 37, 37 and the discharge tube 15 to atmosphere. The valve 34 and the closure 17 are then closed and the receptacle can start to be filled again through the manhole 12.

As an alternative to the elongation receptacle shown in FIGS. 4 and 5, an elongated receptacle can be used which has a funnel-shaped bottom part, the funnel walls forming a chute which extends to a discharge and which has provision for loosening pulverised material, such as air-pervious hoses which are supplied with compressed air. In this case, just as in the case of the vertical receptacle illustrated in FIG. 3, the webs 22, 22 are arranged so that their air-pervious bottom parts come near the funnel wall. 7

Receptacles according to the invention can be used as stationary receptacles (silos or the like) and as receptacles for vehicles.

I claim:

l. in combination with a storage receptacle for sticky powdery material having a discharge outlet centrally of its bottom, a flexible loose lining web normally lying flat against the bottom and inner wall of the receptacle, said web being attached around said discharge outlet and peripherally to the side walls of the receptacle, and means for introducing compressed air between the web and the wall of the receptacle to inflate said web and project the lower portion of said web into a substantially vertical position, said lower portion of said web forming a conduit for the material to be emptied and only said lower portion of said web being pervious to air with all other portions of said web being impervious to air.

2. In combination with a vertical storage receptacle for powdery material having a conical bottom with a central discharge outlet, at flexible loose lining web normally lying flat against the bottom and inner wall of the receptacle, said web being attached around said discharge outlet and peripherally to the side walls of the receptacle, and means for introducing compressed air between the web and the wall of the receptacle to inflate said web and project the lower portion of said web into a substantially vertical position, said lower portion of said web forming a conduit for the material to be emptied and only said lower portion of said web being pervious to air with all other portions of said web being impervi ous to air.

3. In combination with a horizontal storage receptacle for sticky powdery material having a discharge outlet centrally of its bottom, a flexible loose lining web normally lying flat around the. discharge outlet and the inner wall of the lower portion of the receptacle, said web being attached around the discharge outlet and. at an intermediate level around the receptacle, and means for introducing compressed air between the web and the wall of the receptacle to inflate said web and project the lower portion of said web into a substantially vertical position, said lower portion of said web forming a conduit for the material to be emptied and only said lower portion of said web being pervious to air with all other portions of said web being impervious to air.

References Cited by the Examiner UNITED STATES PATENTS 2,930,512 3/60 Paton 222-495 2,956,839 10/60 Hermanns 222193 X 2,968,425 1/61 Paton 222-195 FOREIGN PATENTS 221,562 2/58 Australia.

206,363 11/59 Austria.

213,329 2/61 Austria.

347,766 8/60 Switzerland.

M. 'I-IENSON wooD, IR., Primary Examiner,

LOUIS J. DEMBO, Examiner. 

1. IN COMBINATION WITH A STORAGE RECEPTACLE FOR STICKY POWDERY MATERIAL HAVING A DISCHAREG OUTLET CENTRALLY OF ITS BOTTOM, A FLEXIBLE LOOSE LINING WEB NORMALLY LYING FLAT AGAINST THE BOTTOM AND INNER WALL OF THE RECEPTACLE, SAID WEB BEING ATTACHED AROUND SAID DISCHARGE OUTLET AND PERIPHERALLY TO THE SIDE WALLS OF THE RECEPTACLE, AND MEANS FOR INTRODUCING COMPRESSED AIR BETWEEN THE WEB AND THE WALL OF THE RECEPTACLE TO INFLATE SAID WEB AND PROJECT THE LOWER PORTION OF SID WEB INTO A SUBSTANTIALLY VERTICAL POSITION, SAID LOWER PORTION OF SAID WEB FORMING A CONDUIT FOR THE MATERIAL TO BE EMPTIED AND ONLY SAID 